Xamarin Forms: Custom View (Single Implementation) - xamarin

Question

I've been searching high and low to find an example of how to write a custom UI element that has one implementation (single renderer).
For example, is there a way to simply implement a class that inherits from StackLayout (written in C#) and can then be slotted into other layouts (xaml) as a UI element (similar to how its done using xml views in Android)?
The following is what I have right now, but I am getting errors:
ButtonCustom.xaml.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Xamarin.Forms;
namespace DWalker
{
public partial class ButtonCustom : StackLayout
{
public ButtonCustom()
{
InitializeComponent();
}
public Color TextColor
{
get { return this.Text.TextColor; }
set { this.Text.TextColor = value; }
}
public Label TextControl
{
get { return this.Text; }
set { this.Text = value; }
}
}
}
ButtonCustom.xaml
<?xml version="1.0" encoding="UTF-8"?>
<StackLayout
xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:common="clr-namespace:Dwalker;assembly=DWalker"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
x:Class="DWalker.ButtonCustom">
<Image
x:Name="Icon"
Source="Icon.png" />
<Label
x:Name="Text"
Text="Hello"
HorizontalOptions="Center"
LineBreakMode="NoWrap"
Font="Small"
TextColor="Black"/>
</StackLayout>
Then I'd like to add my custom element to a xaml layouts ContentPage like so:
ViewStart.xaml
<?xml version="1.0" encoding="UTF-8"?>
<ContentPage
xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
xmlns:common="clr-namespace:DWalker;assembly=DWalker"
xmlns:controls="clr-namespace:DWalker;assembly=DWalker"
x:Class="DWalker.ViewStart"
Title="DWalker" >
<AbsoluteLayout>
<controls:ButtonCustom />
</AbsoluteLayout>
</ContentPage>